Association between Mitral Valve Mean Pressure Gradient and Atrial Fibrillation in Patients with Rheumatic Mitral Stenosis: A Cross-Sectional Study.

INTRODUCTION: Atrial fibrillation (AF) often occurs in patients with rheumatic mitral stenosis (RMS) and is associated with adverse clinical outcomes. Mitral valve mean pressure gradient (MVMPG) is utilized as an indicator to assess the severity of mitral stenosis and its hemodynamic implications. The aim of this study was to investigate the association between MVMPG and AF in individuals with RMS. METHODS: We conducted a retrospective analysis of medical records from 360 consecutive patients diagnosed with RMS at the First Affiliated Hospital of Wenzhou Medical University between January 2018 and January 2023. Using both univariate and multivariate logistic regression models, the relationship between MVMPG and AF was evaluated. Restricted cubic splines were employed to test for linearity, and stratified and interaction analyses were performed to evaluate the stability of this relationship among different subgroups. RESULTS: Based on the MVMPG levels, 360 RMS patients in total were categorized into three groups for the analysis: Q1 (<5 mm Hg), Q2 (5-10 mm Hg), and Q3 (>10 mm Hg). The average age was 60.6 years (Q1: 66.1, Q2: 61.9, Q3: 55.8), and 70.8% were female. The prevalence of AF was 39.6%, 56.5%, and 63.2% in Q1, Q2, and Q3, respectively. After adjusting for potential confounders, a significant association between MVMPG and AF was observed. In Q2, there was a 119% increase in AF (OR 2.19, 95% CI: 1.01-4.75), while in Q3, there was a 238% increase (OR 3.38, 95% CI: 1.39-8.19), compared to Q1. The relationship between MVMPG and AF was linear (p = 0.503). These results remained consistent in each subgroup analysis. CONCLUSION: Our study reveals a significant positive association between MVMPG and AF in patients with RMS, which holds important clinical implications. It is necessary to conduct further research.

Fitness effect and transcription profile reveal sublethal effect of nitenpyram on the predator Chrysopa pallens (Neuroptera: Chrysopidae).

Although neonicotinoids are widely used and important insecticide, there are growing concerns about their effect on nontarget insects and other organisms. Moreover, the effects of nitenpyram (NIT), a second generation of neonicotinoid insecticides, on Chrysopa pallens are still unclear. Therefore, this study purposed to investigate the acute toxicity of NIT to C. pallens using the spotting method. To examine the potential effects of a sublethal dose of NIT (LD30 , 1.85 ng of active ingredient per insect) on C. pallens, we constructed the life tables and analyzed the transcriptome data. The life table results showed that the period of second instar larvae, adult pre-oviposition period and total pre-oviposition period were significantly prolonged after exposure to sublethal dose of NIT, but had no significant effects on the other instars, longevity, oviposition days, and fecundity. The population parameters, including the preadult survival rate, gross reproduction rate, net reproductive rate, the intrinsic rate of increase, and finite rate of increase, were not significantly affected, and only the mean generation time was significantly prolonged by NIT. Transcriptome analysis showed that there were 68 differentially expressed genes (DEGs), including 50 upregulated genes and 18 downregulated genes. Moreover, 13 DEGs related to heat shock protein, nose resistant to fluoxetine protein 6, and prophenoloxidas were upregulated. This study showed the potential effects of sublethal doses of NIT on C. pallens and provided a theoretical reference for the comprehensive application of chemical and biological control in integrated pest management.

Risk assessment of airborne agricultural pesticide exposure in humans in rural China.

Continuous exposure to airborne pesticides causes their gradual accumulation in the human body, eventually posing a threat to human health. To the best of our knowledge, risk assessment study of pesticide non-occupational exposure to residents in agricultural areas has not been conducted in China. In this study, air samples (gas and dust) were collected from inside and outside residences of seven households and an area near the field in a grain-growing area (wheat and maize rotation) for eight months, and the pesticides present were examined both qualitatively and quantitatively. Using a 95% confidence interval, 9 out of 16 pesticides were detected, namely acetamiprid, acetochlor, atrazine, flucarbazone-sodium, imidacloprid, methyldisulfuron-methyl, nicosulfuron-methyl, pendimethalin, and beta-cyhalothrin, and their safety was subsequently evaluated. The results showed that the inhalation exposure of households to beta-cyhalothrin exceeded the acceptable range in the first residential, and the excess lifetime cancer risk of acetochlor inhalation exposure in six households and area around the field exceeds 1E-6, which highlights the need to strengthen preventive screening for cancer risk.

Effects of long-term microplastic pollution on soil heavy metals and metal resistance genes: Distribution patterns and synergistic effects.

Heavy metals (HMs) and microplastics (MPs) are two emerging factors threatening global food security. Whether long-term MPs pollution will affect the distribution of HMs and their resistance genes (MRGs) in soil is unknown. Here, metagenomic approach was used to decipher the fate of MRGs in cropland soils with long-term film MPs residues. Similar distribution pattern of MRGs was formed in long-term film MPs contaminated soil. A total of 202 MRG subtypes were detected, with resistance genes for Multimetal, Cu, and As being the most prevalent type of MRGs. MRGs formed a modular distribution of five clusters centered on MRGs including ruvB in long-term film MPs contaminated soil. MRGs also formed tight co-occurrence networks with mobile genetic elements (MGEs: integrons, insertions and plasmids). Redundancy analysis showed that HMs together with microbial communities and MGEs affected the distribution of MRGs in soil. Thirteen genera including Pseudomonas were identified as potential hosts for MRGs and MGEs. The research provides preliminary progress on the synergistic effect of HMs and MPs in affecting soil ecological security. The synergistic effect of MPs and HMs needs to be considered in the remediation of contaminated soils.

Microplastics mulch film affects the environmental behavior of adsorption and degradation of pesticide residues in soil.

Plastic pollution in the soil ecosystem is currently receiving worldwide attention. However, little is known whether the presence of microplastics (MPs) in soil will affect the environmental behavior of pesticide residues in soil. Here, the effect of the addition of new mulch MPs (New-MPs), aged mulch MPs (Aged-MPs) and biodegradable mulch MPs (BioD-MPs) on the adsorption and degradation behaviors of two pesticides (imidacloprid and flumioxazin) in soil was investigated. Three MPs slowed down rapid adsorption stage of pesticides in soil and delayed the time to reach adsorption equilibrium. Adsorption rates: Soil > Soil + New-MPs > Soil + Aged-MPs > Soil + BioD-MPs. Three MPs enhanced the adsorption strength of the soil system for the two pesticides, and the aging treatment of the MPs enhanced this effect. Three MPs affected the degradation process of the two pesticides. New-MPs promoted the degradation of two pesticides imidacloprid and flumioxazin, and the degradation half-lives were shortened to 0.93 and 0.85 times, respectively; while Aged-Mps and BioD-MPs delayed the degradation process of two pesticides, and the degradation half-lives were extended to 1.64 times and 1.21 times, respectively. The effect was more significant with the increase of MPs and pesticides concentration. Pesticide polarity, surface structure and functional groups of MPs are potentially important reasons for the differences in adsorption and degradation of MPs-soil systems. Our findings provide a deep insight into understanding the mechanism of interaction between MPs and pesticide residues in soil environment.

Microbiology combined with metabonomics revealing the response of soil microorganisms and their metabolic functions exposed to phthalic acid esters.

As microplastics became the focus of global attention, the hazards of plastic plasticizers (PAEs) have gradually attracted people's attention. Agricultural soil is one of its hardest hit areas. However, current research of its impact on soil ecology only stops at the microorganism itself, and there is still lack of conclusion on the impact of soil metabolism. To this end, three most common PAEs (Dimethyl phthalate: DMP, Dibutyl phthalate: DBP and Bis (2-ethylhexyl) phthalate: DEHP) were selected and based on high-throughput sequencing and metabolomics platforms, the influence of PAEs residues on soil metabolic functions were revealed for the first time. PAEs did not significantly changed the alpha diversity of soil bacteria in the short term, but changed their community structure and interfered with the complexity of community symbiosis network. Metabolomics indicated that exposure to DBP can significantly change the soil metabolite profile. A total of 172 differential metabolites were found, of which 100 were up-regulated and 72 were down-regulated. DBP treatment interfered with 43 metabolic pathways including basic metabolic processes. In particular, it interfered with the metabolism of residual steroids and promoted the metabolism of various plasticizers. In addition, through differential labeling and collinear analysis, some bacteria with the degradation potential of PAEs, such as Gordonia, were excavated.

Transgenic insect-resistant Bt cotton expressing Cry1Ac/1Ab does not harm the insect predator Geocoris pallidipennis.

The large-scale commercial cultivation of genetically modified (GM) cotton has brought significant economic and environmental benefits. However, GM crops must undergo strict environmental monitoring and long-term observation. An important natural enemy insect in cotton fields, Geocoris pallidipennis, can ingest the Bt protein expressed in GM cotton by feeding on herbivorous insects that feed on the cotton. However, the potential risk of GM cotton to G. pallidipennis is still unclear. We here evaluated the effects of Bt cotton expressing the Cry1Ac/1Ab protein on nymphs and adults G. pallidipennis. Cry1Ac protein was detected in the midgut of the cotton bollworm, Helicoverpa armigera, after it ingested Bt cotton, and in the midgut of G. pallidipennis nymphs and adults preying on Bt-fed H. armigera. However, the survival rate, growth, development, and fecundity of G. pallidipennis were not adversely affected. Furthermore, G. pallidipennis cadherins, and those genes related to detoxification, antioxidant activity, nutrient utilization, and immune function were not differentially expressed in response to Cry1Ac exposure. Finally, we showed that Cry1Ac could not bind to brush border membrane vesicles (BBMV) proteins in G. pallidipennis nymphs or adults. In summary, these results indicate that the potential negative effect of transgenic Cry1Ac/1Ab cotton on the insect redator G. pallidipennis is negligible.

Effect of spraying direction on the exposure to handlers with hand-pumped knapsack sprayer in maize field.

Only less than one percent applied pesticides reach the target pest, the remainder spread out into the environment, effecting on workers, bystanders, consumers and so on. Handlers with manual knapsack sprayer are completely exposed to the pesticide spray plume when they deal with the pesticides. Those kinds of sprayer are widely used in developing countries, more than 75% of farmers using hand-pumped knapsack sprayer in China, yet rarely systematic studies had been focused on the typical applying scenario. The occupational exposure of pesticide is highly correlated with the pesticide spray plume flying time in the air in this scenario. Our study aimed to compare the estimated exposure level of handlers to chlorpyrifos sprayed at three spraying direction using a lever-operated knapsack in small farms in five agro-climatic zones of China. Experiments were performed by 24 farms in each province with three different crop heights (< 80 cm, spraying downward; 80-130 cm, spraying horizontal; and > 130 cm, spraying upward; eight farms for every direction) under typical field conditions. Each farmer covered a uniform area of 667 m2. The whole body dosimetry method and a personal air sampler were used to monitor the dermal and inhalation exposure. The estimated dermal exposure of the three spraying direction was 629, 1580, and 2140 mg/kg, respectively. The results showed that the total dermal exposure level increased with the spraying direction from downward to upward. Furthermore, appropriate cotton coveralls could reduce more than 90% of the total dermal exposure.

[Study on the hemodynamic changes in solid thyroid nodules by ultrasound contrast quantitative analysis].

OBJECTIVE: To compare the difference between the different perfusional regions in solid thyroid nodules. METHODS: From October 2013 to May 2015, CEUS was performed in 59 patients who hospitalizated in Zhoushan Hospital with solid thyroid nodules before operation. The time-intensity curve (TIC) of normal thyroid tissue, tumor edge and tumor center was drawn to collect perfusion index like the peak intensity (PI), time to peak (TP), area under the curve (AUC), mean transit time (MTT). After surgery, immunohistochemical staining was performed to evaluate the MVD in surgical specimens.Quantitative parameters and MVD were assessed by the Spearman correlation analysis. RESULTS: There were 31 thyroid papillary carcinomas and 28 nodular goiters. In malignant tumor group, the PI of normal thyroid tissue, tumor edge and tumor center were 28% ± 6%, 21% ± 7% and 14% ± 5%, respectively, while the AUC and MVD of the same regions were (1 865 ± 1 079)%S, (1 376 ± 595)%S, (805 ± 412)%S and(33 ± 6), (27 ± 6)/HP, (17 ± 6)/HP, respectively. The differences were statistically significant. However, in benign tumor group, there was no obvious statistic difference in the quantitative parameters and MVD between the three regions. The PI values of thyroid carcinomas and nodular goiters all were positively correlated with MVD (r=0.819, r=0.838, P<0.05). CONCLUSIONS: The variance of perfusion parameters were valuable diagnostic basis in differential diagnosis between benign and malignant thyroid nodules. They were associated with MVD, which might reflect the microvessel distributional characteristics of neoplasm and might be one of bases used to evaluate neoplasm angiogenesis.

Exploring the potential of biochar for the remediation of microbial communities and element cycling in microplastic-contaminated soil.

The detrimental effects of microplastics (MPs) on soil microbial and elemental raise significant environmental concerns. The potential of remediation with biochar to mitigate these negative impacts remains an open question. The remediation effects of biochar derived from corn and cotton straw on MPs concerning soil microorganisms and element cycling were investigated. Specifically, biochar induced substantial remediations in microbial community structure following MP exposure, restoring and fortifying the symbiotic network while exerting dominance over microbial community changes. A combined treatment of biochar and MPs exhibited a noteworthy increase in the abundance of NH4+, NO3-, and available phosphorous by 0.46-2.1 times, reversing the declining trend of dissolved organic carbon, showing a remarkable increase by 0.36 times. This combined treatment also led to a reduction in the abundance of the nitrogen fixation gene nifH by 0.46 times, while significantly increasing the expression of nitrification genes (amoA and amoB) and denitrification genes (nirS and nirK) by 22.5 times and 1.7 times, respectively. Additionally, the carbon cycle cbbLG gene showed a 2.3-fold increase, and the phosphorus cycle gene phoD increased by 0.1-fold. The mixed treatment enriched element-cycling microorganisms by 4.8 to 9.6 times. In summary, the addition of biochar repaired the negative effects of MPs in terms of microbial community dynamics, element content, gene expression, and functional microbiota. These findings underscore the crucial role of biochar in alleviating the adverse effects of MPs on microbial communities and elemental cycling, providing valuable insights into sustainable environmental remediation strategies.

Impact of a glyphosate-based herbicide on the longevity, fertility, and transgenerational effects on Chrysopa pallens (Rambur) (Neuroptera: Chrysopidae).

Glyphosate-based herbicides (GBHs) are common herbicide formulations used in the field and are increasingly used worldwide with the widespread cultivation of herbicide-tolerant genetically modified crops. As a result, the risk of arthropod exposure to GBH is increasing rapidly. Chrysopa pallens (Rambur) (Neuroptera: Chrysopidae) is a common predatory natural enemy in agroecosystems, which is exposed to GBH (Roundup®) while preying on pests. To identify and characterize the potential effects of GBH on C. pallens, the life tables of C. pallens larvae and adults fed with GBH were constructed. Moreover, the effects of GBH treatment on the expression of genes involved in insulin signalling in adults were analyzed using qRT-PCR. The results showed that GBH treatment altered the pupal period and preadult stage of C. pallens larvae. However, it did no effect on longevity, fecundity, and population parameters and two insulin receptor genes (InR1, InR2), a serine/threonine kinase (Akt), an extracellular-signal-regulated kinase (erk), and vitellogenin (Vg1) expression of C. pallens. Adults feeding on GBH significantly altered development, longevity, and differences in the mean generation time of the F0 generation. However, GBH feeding only minimally influenced the growth and population parameters of the F1 generation. In addition, InR1, InR2, erk, and Vg1 expression in the F0 generation were downregulated on the fifth day of feeding on GBH. Furthermore, the expression levels of InR1, InR2, Akt, erk, and Vg1 in C. pallens decreased with the increase of GBH concentration, although the expression levels returned to control levels on the tenth day. Overall, the consumption of the GBH by larvae and adults of C. pallens had minimal effect on the growth and population parameters of C. pallens. The findings of this study can provide a reference for elucidating the environmental risks of GBH, guiding the optimal use of glyphosate in agricultural practices in the future.

Combined effects of mulch film-derived microplastics and pesticides on soil microbial communities and element cycling.

Pesticides and microplastics (MPs) derived from mulch film in agricultural soil can independently impact soil ecology, yet the consequences of their combined exposure remain unclear. Therefore, the effects of simultaneous exposure to commonly used pesticides (imidacloprid and flumioxazin) and aged mulch film-derived MPs on soil microorganisms and element cycles in cotton fields were investigated. The combined exposure influenced soil microorganisms, alongside processes related to carbon, nitrogen, and phosphorus cycles, exhibiting effects that were either neutralized or enhanced compared to individual exposures. The impact of pesticides in combined exposure was notably more significant and played a dominant role than that of MPs. Specifically, combined exposure intensified changes in soil bacterial community and symbiotic networks. The combined exposure neutralized NH4+, NO3-, DOC, and A-P contents, shifting from 0.33 % and 40.23 % increase in MPs and pesticides individually to a 40.24 % increase. Moreover, combined exposure resulted in the neutralization or amplification of the nitrogen-fixing gene nifH, nitrifying genes (amoA and amoB), and denitrifying genes (nirS and nirK), the carbon cycle gene cbbLG and the phosphorus cycle gene phoD from 0.48 and 2.57-fold increase to a 2.99-fold increase. The combined exposure also led to the neutralization or enhancement of carbon and nitrogen cycle functional microorganisms, shifting from a 1.53-fold inhibition and 10.52-fold increase to a 6.39-fold increase. These findings provide additional insights into the potential risks associated with combined pesticide exposure and MPs, particularly concerning soil microbial communities and elemental cycling processes.

Tank-Mix Adjuvants Enhance Pesticide Efficacy by Improving Physicochemical Properties and Spraying Characteristics for Application to Cotton with Unmanned Aerial Vehicles.

Tank-mix adjuvants have been used to reduce spray drift and facilitate the efficacy of pesticides applied with unmanned aerial vehicles (UAVs). However, the effects of specific adjuvants on pesticide characteristics and the mechanism of action remain unclear. Herein, we analyzed the effects of three different types of tank-mix adjuvants (plant oil; mineral oil; and mixture of alcohol and ester) on the surface tension (ST), contact angle, wetting, permeation, evaporation, spray performance, and aphid-control effects of two types of pesticides. The mineral oil adjuvant Weichi (WCH) was highly effective in reducing the pesticide solution ST, improving the wetting and penetration ability, increasing droplet size, and promoting droplet deposition. The mixed alcohol and ester adjuvant Quanrun (QR) showed excellent wetting and antievaporation properties and promoted droplet deposition. A plant oil adjuvant (Beidatong) moderately improved wetting and penetration ability and reduced droplet drift. Field tests showed that the control efficiencies (CEs) of two pesticides were increased after the addition of adjuvants, even with 20% reductions in pesticide application. When the UAV was operated at 1.5 m, the CEs of two pesticides were increased from 65.39 and 66.63% to 73.11-76.52% and 77.91-88.31%, respectively. When operated at 2.5 m, the CEs were increased from 51.24 and 68.60% to 65.06-75.70% and 77.57-92.59%, respectively. Especially, the CEs of pesticides with WCH and QR increased obviously. Importantly, neither WCH nor QR inhibited hatching of the critical insect natural enemy ladybird beetle at concentrations used in the field. This study provides a framework for assessment of tank-mix adjuvants in aerial sprays and directly demonstrates the value of specific adjuvants in improving pesticide bioavailability and minimizing associated environmental pollution.

Tracking antibiotic resistance genes in microplastic-contaminated soil.

Agricultural soils and microplastics (MPs) are hotspots for antibiotic resistance genes (ARGs). Plastic mulch is the most important source of MPs in agricultural soil. ARGs, mobile genetic elements (MGEs), and their host profiles in long-term mulch MP-exposed soils remain unclear. In the present study, metagenomics was used to investigate the distribution patterns of ARGs and MGEs in eight Chinese provinces with a long history of plastic mulch use. A total of 204 subtypes of ARGs and thousands of MGEs (14 integrons, 28 insertions, and 2993 plasmids) were identified. A similar diversity of ARGs was found among MPs film-contaminated sites. The types of ARGs with a high abundance were more concentrated, and multidrug resistance genes were the dominant ARGs. Soils from regions with a longer history of plastic film use (such as Xinjiang province) had a higher abundance of ARGs and MGEs. The distribution of ARGs and MGEs exhibited a modular network distribution pattern. A total of 27 ARG subtypes and 29 MGEs showed co-occurrence network relationships. More than 10 common hosts of ARGs and MGEs, such as Pseudomonas, were found, and their abundances were highest in three provinces, including Xinjiang. This study may help elucidate the impact mechanism of long-term MP residues on the occurrence and spread of ARGs in soil.

Integrated microbiology and metabolomics analysis reveal plastic mulch film residue affects soil microorganisms and their metabolic functions.

Research on microplastic pollution of terrestrial soils is catching up with the aquatic environment, especially agricultural soil systems. Plastic residues have caused various environmental problems in mulch film extensively used agricultural areas. However, studies focusing specifically on the potential influence of mulch film residues on the metabolic cycle of soil systems have yet to be conducted. Here, high-throughput sequencing combined with metabolomics were first used to study the effects of residual mulch on soil microbial communities and related metabolic functions. Plastic film treatment did not significantly affect soil physicochemical properties including pH, organic matter and nitrogen, etc in short term. However, it did significantly changed overall community structure of soil bacteria, and interfered with complexity of soil bacterial symbiosis networks; exposure time and concentration of residues were particularly important factors affecting community structure. Furthermore, metabolomics analysis showed that film residue significantly changed soil metabolite spectrum, and interfered with basic carbon and lipid metabolism, and also affected basic cellular processes such as membrane transport and, in particular, interfered with the biosynthesis of secondary metabolites, as well as, biodegradation and metabolism of xenobiotics. Additionally, through linear discriminant and collinear analysis, some new potential microplastic degrading bacteria including Nitrospira, Nocardioidaceae and Pseudonocardiaceae have been excavated.

Gut Bacterial Diversity in Different Life Cycle Stages of Adelphocoris suturalis (Hemiptera: Miridae).

Bacteria and insects have a mutually beneficial symbiotic relationship. Bacteria participate in several physiological processes such as reproduction, metabolism, and detoxification of the host. Adelphocoris suturalis is considered a pest by the agricultural industry and is now a major pest in cotton, posing a serious threat to agricultural production. As with many insects, various microbes live inside A. suturalis. However, the microbial composition and diversity of its life cycle have not been well-studied. To identify the species and community structure of symbiotic bacteria in A. suturalis, we used the HiSeq platform to perform high-throughput sequencing of the V3-V4 region in the 16S rRNA of symbiotic bacteria found in A. suturalis throughout its life stages. Our results demonstrated that younger nymphs (1st and 2nd instar nymphs) have higher species richness. Proteobacteria (87.06%) and Firmicutes (9.43%) were the dominant phyla of A. suturalis. At the genus level, Erwinia (28.98%), Staphylococcus (5.69%), and Acinetobacter (4.54%) were the dominant bacteria. We found that the relative abundance of Erwinia was very stable during the whole developmental stage. On the contrary, the relative abundance of Staphylococcus, Acinetobacter, Pseudomonas, and Corynebacterium showed significant dynamic changes at different developmental stages. Functional prediction of symbiotic bacteria mainly focuses on metabolic pathways. Our findings document symbiotic bacteria across the life cycle of A. suturalis, as well as differences in both the composition and richness in nymph and adult symbiotic bacteria. Our analysis of the bacteria in A. suturalis provides important information for the development of novel biological control strategies.

Characterization and comparison of the bacterial microbiota of Lysiphlebia japonica parasitioid wasps and their aphid host Aphis gosypii.

BACKGROUND: Endosymbiotic bacteria have been reported to mediate interactions between parasitoids and their insect hosts. How parasitic wasps influence changes in host microbial communities and the relationship between them are of great importance to the study of host-parasitoid co-evolutionary and ecological interactions. However, these interactions remain largely unreported for interactions between Aphis gossypii and Lysiphlebia japonica. RESULTS: In this study, we characterize the bacterial microbiota of L. japonica wasps at different developmental stages and monitor changes over time in the bacterial microbiota of their parasitized and nonparasitized aphid hosts, using metagenomic analysis of 16S rDNA sequencing data. Proteobacteria, Firmicutes, and Actinobacteria were the three most abundant bacterial phyla identified in L. japonica. We found that parasitism was associated with an increased abundance of Buchnera nutritional endosymbionts, but decreased abundance of Acinetobacter, Arsenophonus, Candidatus_Hamiltonella, and Pseudomonas facultative symbionts in aphid hosts. Functional analysis of enriched pathways of parasitized aphids showed significant differences in the 'transport and metabolism of carbohydrates' and 'amino acid, lipid, and coenzyme biosynthesis' pathways. Notably, the composition of symbiotic bacteria in wasp larvae was highly similar to that of their aphid hosts, especially the high abundance of Buchnera. CONCLUSION: The results provide a conceptual framework for L. japonica interactions with A. gossypii in which the exchange of symbiotic microbes provides a means by which microbiota can potentially serve as evolutionary drivers of complex, multilevel interactions underlying the ecology and co-evolution of these hosts and parasites. © 2021 Society of Chemical Industry.

Influence of the neonicotinoid insecticide thiamethoxam on soil bacterial community composition and metabolic function.

Understanding of neonicotinoid insecticides toxicity on non-target organisms, such as bees, has indirectly promoted their soil treatment use. However, their effect on soil ecosystems haven't fully understood. Here, based on 16S rRNA high-throughput sequencing and metagenomics, the effects of neonicotinoid insecticide thiamethoxam on bacterial communities and metabolic functions in two types of soils were studied. Thiamethoxam treatment significantly affected soil bacterial abundance, reduced microbial diversity, and changed the bacterial community structure in the short term, and the structure soon returned to a stable state. Soil type and time were important factors affecting bacterial community structure. Some plant growth-promoting rhizosphere bacteria (PGPR) including Actinobacteria were found, and their populations were reduced, while pollutant-degrading bacteria including Firmicutes were also found, and their populations were increased. Based on metagenomics analysis, thiamethoxam treatment insignificantly promoted or inhibited multiple metabolic processes, but gene abundance of some key processes significantly changed. Subtypes of 18 biodegradation genes (BDGs) and 5 pesticide degradation genes (PDGs) were identified. Thiamethoxam treatment significantly increased the abundance of BDGs and PDGs, including cytochrome P450. Potential hosts of P450 degradation genes, including the genus Rhodococcus, were discovered. Conclusions of this study will promote safety evaluation and degradation-related research on neonicotinoid insecticides in soil.

Glyphosate exposure disturbs the bacterial endosymbiont community and reduces body weight of the predatory ladybird beetle Harmonia axyridis (Coleoptera: Coccinellidae).

The predatory ladybird beetle, Harmonia axyridis, is a predominant natural enemy of pest insects in cotton fields. Commercialization of genetically modified crops has promoted the increased use of the herbicide glyphosate. In this study, to assess potential negative effects of glyphosate on beneficial non-target organisms in cotton fields, we first examined how glyphosate exposure affected the development and endosymbiotic bacterial community of H. axyridis. The results showed that the survival rate, development duration, pupation rate and emergence rate of H. axyridis under low and high concentrations of glyphosate exposure were not significantly changed, but glyphosate did significantly reduce the body weight of H. axyridis. Based on 16S rRNA sequencing, there were no significant differences in the diversity or richness of the endosymbiotic bacteria of H. axyridis before and after glyphosate exposure. The dominant bacterial phyla Firmicutes and Proteobacteria and genera Staphylococcus and Enterobacter remained the same regardless of treatment with glyphosate, however the abundance and copy number of these bacteria were altered. Glyphosate treatment significantly reduced the abundance and gene copy number of Staphylococcus and increased the abundance and gene copy number of Enterobacter. This is the first report demonstrating that glyphosate can reduce the body weight H. axyridis and alter the bacterial endosymbiont community by affecting the abundance and gene copy number of dominant bacteria.

Evaluation of sublethal and transgenerational effects of sulfoxaflor on Aphis gossypii via life table parameters and 16S rRNA sequencing.

BACKGROUND: Aphis gossypii, a polyphagous and recurrent pest induced by pesticides, causes tremendous loss crop yields each year. Previous studies on the mechanism of pesticide-induced sublethal effects mainly focus on the gene level. The symbiotic bacteria are also important participants of this mechanism, but their roles in hormesis are still unclear. RESULTS: In this study, life table parameters and 16S rRNA sequencing were applied to evaluate the sublethal and transgenerational effects of sulfoxaflor on adult A. gossypii after 24-h LC20 (6.96 mg L-1 ) concentration exposure. The results indicated that the LC20 of sulfoxaflor significantly reduced the finite rate of increase (λ) and net reproductive rate (R0 ) of parent generation (G0), and significantly increased mean generation time (T) of G1 and G2, but not of G3 and G4. Both reproductive period and fecundity of G1 and G2 were significantly higher than those of the control. Furthermore, our sequencing data revealed that more than 95% bacterial communities were dominated by the phylum Proteobacteria, in which the maximum proportion genus was the primary symbiont Buchnera and the facultative symbiont Arsenophonus. Compared to those of the control, the abundance and composition of symbiotic bacteria of A. gossypii for three successive generations (G0-G2) were changed after G0 A. gossypii was exposed to sulfoxaflor: the diversity of the bacterial community was decreased, but the abundance of Buchnera was increased (G0), while the abundance of Arsenophonus was decreased. Contrary to G0, G1 and G2 cotton aphid exhibited an increased relative abundance of Arsenophonus in the sublethal treatment group. CONCLUSION: Taken together, our results provide an insight into the interactions among pesticide resistance, aphids, and symbionts, which will eventually help to better manage the resurgence of A. gossypii. © 2021 Society of Chemical Industry.